Direct broadcast systems offer various different services including video and audio programming. Additional new services are continuously being offered for direct satellite broadcast system users. In order to offer these various services, multiple primary servers are controlled to transmit the audio and video programming over multiple channels and designated time frames.
Uninterrupted play-out of the audio and video programming is required in direct broadcast systems. In a direct broadcast environment every second of “airtime” is important and interrupted airtime can be costly. Airtime is especially important during pay-per-view and commercial time frames. When a commercial or pay-per-view event is interrupted for just one or two seconds, revenue is lost.
It is therefore critical that there be a backup scheme associated with each primary server. Typically, a one-to-one backup scheme is used. The one-to-one backup scheme includes operating a backup server in parallel with each primary server. With this configuration, when a failure occurs in a primary server, a backup server assumes the play-out role of the inoperative or improperly operating primary server. Thus, full redundancy exists in the event of failure of any or all of the primary servers.
The one-to-one backup scheme, however, has several associated disadvantages. Since there is a backup server or other backup device operating in parallel with each primary server the cost of providing, maintaining, and operating the backup broadcast system is relatively high. Additionally, in the event that both a primary server and an associated backup server malfunction simultaneously, there may be a large amount of downtime, sometimes several hours, before the primary server of interest is repaired/replaced or a second backup server is installed.
Also, backing up a group of primary servers with a backup tape is not a viable solution as there may be several minutes of delay in cueing the tape to point where the primary tape failure, before playback can occur. This is not tolerable, as even a mere 1 or 2 second delay can result in loss of customers and/or revenue.
Statistically there are times in programming in which typical malfunctions are more likely to occur such as the beginning portion of a program or commercial. There are also times where the cost of failure is higher than others. It is at these times when backup and the manner as to which the backup is performed is most critical. Existing backup systems do not account for the portion of a program or commercial that is at higher risk of failure or has a higher cost of failure in any different or better fashion than the remainder of the program or commercial.
It would therefore be desirable to minimize the number of backup servers and components within a direct broadcast system while also providing a backup system that minimizes downtime, virtually eliminates any switch over time, and takes into account the programming or portions of programming that have a high-probability or high cost of failure.